On-a-Chip-Based Sensitive Detection of Drug-Induced Apoptosis in Polarized Gastric Epithelial Cells

Microfluidic
devices for culturing cells have been successfully
utilized for biomedical applications, including drug screening. Several
cell lines could be cultivated in microengineered environments with
promising results, but gastric cell lines have not yet been widely
used or studied. Therefore, this study focuses on establishing a polarized
gastric epithelial monolayer on-a-chip and describes a general-purpose
methodology applicable for bonding any porous material to PDMS through
an adhesive sublayer. The fully transparent microfluidic chip consists
of two microfluidic channels separated by a collagen-coated porous
membrane and lined by human polarized gastric epithelial (NCI-N87)
cells. We present considerations on how to ensure continuous and stable
flow through the channels. The continuous flow rate was achieved using
a pressure-driven pump. Media flow at a constant rate (0.5 μL/min)
rapidly led the gastric epithelial cells to develop into a polarized
monolayer. The barrier integrity was assessed by the FITC-dextran
test. The generation of a monolayer was faster than in the static
Boyden chamber. Moreover, fluorescence microscopy was used to monitor
the apoptotic cell death of gastric epithelial monolayers on-a-chip
in response to camptothecin, a therapeutic gastric cancer drug.